Jennifer Lopez and Casper Smart headed for split

The 'On The Floor' singer has been planning to dump her backing dancer beau after the "spark" began to disappear from their two year relationship, and its reported they already had a short break-up earlier this summer.

A source revealed to RadarOnline: "Jennifer is pretty private about the relationship, but she's been hinting that the spark is gone.She's having a hard time ignoring the fact her head has been telling her for a while that this thing with Casper isn't forever. And now her heart's saying the same thing.

"She enjoyed the relationship for what it is, but now that giddiness has turned to sadness."

Jennifer and her 25-year-old beau, haven't been pictured together for three weeks, and its believed she has cancelled their high-profile appearances together after she attended the Human Rights Campaign national dinner in Washington D.C solo earlier this month.

A source said: "Jennifer's team started scheduling all her major appearances solo," the source says. But Lopez eventually took him back -- for now."

The reason Jennifer reportedly hasn't called quits on her romance is because of Casper's close relationship with her twins, Max and Emme - who she had with her ex-husband Marc Anthony.

The source added: "It's hard for her to think of how to it explain it to the twins,they love Casper. Jennifer's probably going to at least stay friends with him so hopefully it won't be as dramatic as it's been talking to them about her split from their dad."

The last time the couple was seen together was during night out in Los Angeles in September. (21.09.13)